The present invention relates to rheumatology. In particular, the invention relates to the use of a known substance, Somatostatin, in the treatment of rheumatic states and, particularly, inflammatory articular diseases.
Inflammatory articular diseases, both acute and chronic, characterised by a phlogistic involvement of the synovial membrane with subsequent cartilage and bone damage, are very common. The most typical inflammatory articular disease is Rheumatoid Arthritis (RA) where, as in the case of arthrosis (degenerative disease of the cartilage with possible phlogistic involvement), all the symptomatic, analgesic and anti-inflammatory drugs, and other treatments such as gold salts, anti-malaria medicines and penicillamine, are used at present with the aim of modifying the trend of the disease.
Typical articular diseases of inflammatory character are, for example, gout, Sjogren's syndrome, ankylopoietic spondilitis, intermittent hydrarthrosis, the consequences of trauma and forms of arthrosis with inflammatory involvement, as well as the above mentioned adult Rheumatoid Arthritis and its infantile and juvenile variations.
The aetiology of RA is still unknown. Various hypotheses include aetiopathogenetic events of the psychosomatic type (nervous theory), or the cause is considered to be an altered metabolism due to hepatic dysfunction (metabolic theory), or else an infective aetiopathogenesis (infectious theory), or finally, RA is classified among the diseases due to hypersensitivity (immunitary theory). The latter is the most accredited theory at present.
Symptomatic therapy of RA and, more generally, of inflammatory articular diseases, is based on medicines with antiphlogistic and analgesic properties such as cortisonics and non-steroidal anti-inflammatory drugs (NSAIDs).
Fundamental therapy is based on synthetic anti-malaria drugs, e.g. chloroquine phosphate, gold salts, penicillamine and certain immunosuppressor drugs such as azathioprine and cyclophosphamide.
All the above indicated therapies, other than not being remedial therapies for inflammatory articular diseases in general, and even less in the case of RA, are also inconvenient in that they make recourse to drugs which have more or less severe side effects and often contraindications which render inadvisable their use in the treatment of many patients, especially when treatment is long-term, as is the case with this kind of disease.
Therefore, in the field of rheumatology, a great need is felt for a treatment of RA and other inflammatory articular diseases employing efficacious drugs which are substantially devoid of side-effects and contra-indications.
Somatostatin (SS) is a peptidic hormone originally studied for its inhibitory effect on secretion by the hypophysis of the growth-hormone, also known as Somatotrophin. Due to this property, SS is also known as SRIF (Somatotrophin Release Inhibiting Factor).
Originally isolated from bovine and ovine hypothalami, Somatostatin has a well known structural formula and is currently produced by chemical synthesis.
The structure of the Somatostatin cyclic tetradecapeptide is the following: ##STR1## Recent studies have shown that Somatostatin is capable of inhibiting gastric secretion, endocrine pancreatic secretion, the secretion of glucagon, and of reducing the blood flow in the splanchnic area without determining significant variations in arterial pressure.
More recently, the inhibitory effect of Somatostatin on the secretion of the growth hormone has been correlated with the recognized therapeutic effect of Somatostatin in severe cases of psoriasis. The real mechanism is still the object of further studies.
Furthermore, Somatostatin has been found efficacious in the treatment of idiopathic headache, especially migraine and cluster headache.